Albany 2015:Book of Abstracts

Origin and evolution of adaptive immunity systems

Comparative genomics reveals unexpected, striking parallels between the evolutionary scenarios inferred for adaptive immunity systems in prokaryotes, ciliates and animals. The CRISPR-Cas mechanism of adaptive immunity in archaea, the IES-Ias defense system in ciliates and the vertebrate adaptive immunity that is centered on V(D)J recombination all appear to have evolved via similar scenarios. Each of these defense systems emerged through integration of a transposable elements into innate immunity loci in the respective genomes. Strikingly, neither the transposons nor the innate immune machineries involved are homologous. Thus, the unexpected parallelism between the origins of these unrelated defense mechanisms reveals general principles of evolution of genome manipulation strategies and also explains the remarkable efficiency of adaptive immunity systems as tools of molecular biology (Chylinski et al., 2014; Koonin and Krupovic, 2015a; Koonin and Krupovic, 2015b; Krupovic et al., 2014).

This research was supported by Intramural fund of the US Department of Health and Human Services (to National Library of Medicine)